routes.jsx

// V5
<Router>
  <Switch>
    <Route path="/one" component={ViewOne} />
    <Route path="/two" component={ViewTwo} />
    <Route path="/three" component={ViewThree} />
    <Route render={() => <Redirect to="/one" />} />
  </Switch>
</Router>

// V6
<Router>
  <Routes>
    <Route path="/one" element={<ViewOne />} />
    <Route path="/two" element={<ViewTwo />} />
    <Route path="/three" element={<ViewThree />} />
    <???>
  </Routes>
</Router>


// Possible new way of handling
<Router>
  <Routes>
    <Route path="/one" element={<ViewOne />} />
    <Route path="/two" element={<ViewTwo />} />
    <Route path="/three" element={<ViewThree />} />
    <Route path="*" element={<SelfRedirect path="/one" />} />
  </Routes>
</Router>

const SelfRedirect = ({ path }) => {
  let navigate = useNavigate();
  
  useEffect(() => {
    navigate(path);
  });
}